1. Field of the Invention
The present invention relates generally to the design and operation of antennae, and particularly to antennae that can be folded and compactly stored.
2. Description of the Background
Antennas have been fabricated of many materials in numerous forms for nearly a century. Fundamental to all antennas is the use of electrically conductive material to form the electrical fields needed to radiate electromagnetic energy as a propagating radio wave. Materials that are good electrical conductors are metallic, e.g. Gold, Silver, Copper, Aluminum, or they are metallic alloys, e.g. Brass, Bronze, Stainless Steel, etc. The nature of most metals and metal alloys is their tendency to be rigid, brittle, or malleable such that they do not return to the original form after being stressed as tends to occur during transport and repositioning. This behavior causes portable or transportable antenna designs to be highly susceptible to damage resulting from shock, impact, dropping, or other mishandling during transport and deployment.
The shape and form of electrically conductive components used to form antennas is an integral part of the antenna design such that variations to this shape, caused by stress or other damage, alter the performance in a significant and unpredictable manner. Once damaged, antennas rarely, if ever, perform as intended.
Metals used for antennas are generally protected from damage due to environmental effects, such as corrosion and rust, with protective coatings like paint. Generally, the metallic components are not protected from physical damage or are segmented into smaller sections with joints that can fail, necessitating component replacement. In some situations, conductive wires comprised of a plurality of small strands of metallic conductors grouped together via weaving, wrapping, or over coating in a flexible non-conducting material are used to mitigate the damaging effects of bending. However, the metallic conductors, if exposed to excessive flexure or small radius bending will deform and not return to their initial shape.
In portable or transportable applications, the metallic conductors used to form the radiating structures of antennas are damage prone. Once exposed to excessive flexure, physical blows, or small radius bending, such as occur during transportation, handling, and deployment, these conductive elements deform and alter the performance of the antenna in an unacceptable manor. Field expedient repairs and reforming of damaged components rarely, if ever, yields a serviceable solution. More likely, the bending of the antenna component results in a localized hardening of the component at the molecular level known as “work hardening”. Once bent and hardened into the wrong position, re-bending to the proper position typically results in a fracture and total failure of the component.